I. Field of the Invention
This invention relates generally to a urinary catheter, and more particularly to a urinary catheter for temporary relief of symptoms due to benign prostatic hypertrophy (BPH).
II. Discussion of the Prior Art
Enlargement of the prostatic gland is common among men after 50 years of age. The condition is not malignant nor inflammatory, but may lead to obstruction of the urethra, interfering with the flow of urine. This can increase frequency of urination, the need to urinate during the night, pain and urinary tract infections.
The prostate gland itself is somewhat walnut-shaped and surrounds the urethra just below the neck of the urinary bladder. With BPH, the prostate may significantly narrow the urethra causing the above problems. A procedure called transurethral resection of the prostrate is often used to remove some of the tissue comprising the prostate gland to reduce its size and thereby leave the urethra unobstructed. Because of the discomfort associated with this surgery, many males shun it until the process progresses to the point where a drainage catheter, such as the well known Foley catheter, is used to continuously drain the urinary bladder into a urine collection bag. A Foley catheter comprises a double lumen tube adapted to be inserted into the urethra through the meatus thereof and advanced until its distal end resides in the urinary bladder. The first lumen comprises an inflation lumen for causing an expandable balloon on the distal end portion of the catheter to be inflated. The inflated balloon serves to hold the drainage catheter in place. There is an opening at the distal end of the second lumen through which urine can flow through the length of the catheter to the collection bag. With such a catheter installed, the patient has no control over the elimination of urine from the bladder.
The Foley catheter has another drawback. Because urine drips through the lumen of the catheter, the walls of the urethra are not periodically bathed during urination, resulting in an increase in urinary infection. Thus, the catheter must be periodically removed and replaced to avoid the growth of bacteria between the wall of the catheter and the lining of the urethra.
A need therefore exists for draining the bladder without the above-recited difficulties associated with the use of a Foley catheter. The device must maintain the prostatic urethra patent in patients with BPH while still allowing the patient to utilize his urinary sphincter for controlling the elimination of urine from the bladder. The device should also permit it to be disposed in the patient's urethra for extended periods without increasing the likelihood of infection.